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The 677-9149-01 is the part number. but its an obsoleted number. Should be able to get them from most HVAC parts supply houses, if they will sell to you. Other wise you'll have to go to Grainger, or order them over the internet.

The 677-9149-01 is the part number. but its an obsoleted number. Should be able to get them from most HVAC parts supply houses, if they will sell to you. Other wise you'll have to go to Grainger, or order them over the internet.

Thanks. A buddy of mine clued me in on how it may be difficult to buy Lennox parts from a supply house. I may have located the 677-9149-01 on E-bay. One from CozyParts. com is CAPACITOR-START 189-277 MFD 330 VAC, 72H7201$86.43 . That seems ridiculously high given what seems to be equivalent parts on E-bay run betweem $7 and $23. As long as it physically fits, is rated 189-277 MFD 330 VAC, can I by one of these off of E-bay or at any supply house. A large one in Santa Fe Springs has one for $12 and I can find a reason to get out that way.

I also located a dual capacitor replacement on CozyParts for $30 which I can live with. It isn't listed in this Santa Fe Springs outfit's online catalog but I will call to see if they have one. It probably is local to So Cal but it's called McMasters-Karr.

I don't want to get too much into this because I guess the compressor may still be bad.

The start can remain 330 volt. The capacitor VAC rating is only for its internal electrical insulation.

Cool.

I remetered after replacing all disconnects. On the new meter the ohms fluctuate (for instance what measures 1.0 goes to 1.1 and back and occasionally reads 0.9 or 1.2) I also retook the ohms with the old digital adjusted for resistance across the prongs. I got a 2.3., 1.2 (sometimes reading 1.1), and a 1.1. I now realize that the sum of the start and run winding should equal the third. It appears they do that if I disregard the fluctuations on the one that produces extremes of .9 and 1.2)

Reading further, I understand that the start winding should be have much higher resistance than the run winding. As measured, they are nearly equal.

I also realized that my new meter has an infinity reading (as I think the old one does) All 3 wires measured 1.L (infinity) to ground. I believe that does not mean there is no short as the meter may not be senitive enough to detect a short.

Does the fact that run and start windings have nearly equal resistance indicate anything. I do note that the start and run windings of the fan have more measurable difference (27.8 to 21.4). The the fan works with the compressor windings disconnected.

That is cause whenn you measure resistance from s to r you are actually measuring the combined resistance of the start and run windings that are connected in series at the common terminal.

I think it is time to get some quotes on a new compressor unit. Hopefully I can get something to basically drop on the existing pad and hook up with the existing system without much additional expense. I even placed a call to guy recommended by someone who is with a local HVAC service business.

I retested the capacitors with the Klein meter and this time the start capacitor checked out with 213.8 MFD. It is rated 189 to 227 MFD. Still, the common to hermes side of the dual run capacitor only measures a couple of nF (rated 60 MFD) while the run side is 10.49 MFD (Rated 10 MFD).

beenthere is likely prescient about a short between the start and run windings. but I ordered a dual capacitor. It is probably a wasted $40 but will give it a try.

I replaced the dual run capacitor that had a dead hermes side. It made no diference.

I also bought a better multi meter, a Klein MM1000, and reread the condensor windings; not just at the disconnected wires in the control box but I took my readings off of the terminals on the condensor.

C to S: 2.7 to 2.8 Ω
C to R: 3.1 Ω
S to R: 4.4 to 4.5 Ω

I also rechecked resistance from terminals to the condensor crank case, which was done after I scraped the paint off a spot. The same readings were obtained when resistance was read to the copper suction pipe instead of the crank case.

The readings were greatly differen

t if I probed the terminal with red and the crank case with black or if I swithed them.

Black probe to copoper and Red to any condensor terminal: about 4.65 MΩ creeping up to over 5 MΩ.
Red probe to copper and black to any condensor terminal: 14 MΩ creeping up to over 15 MΩ.

Whe I say it was creeping resistance was climbing at a rate of about .01 MΩ per second and I didn't wait to see how high it would eventually climb.

Is it at all likely that the problem is a bad contactor. It pulls in when the thermostat is switched on at which time a large spark is seen between the points connecting the load and line side of L1. Aat the very instant the circuit breaker pops. The wires connecting the common and the run terminals of the condensor to the two load sides of the contactor were pretty badly fried at that point. The insulation on one was melted right at the disconnects and the disconnect on one side had gotten so hot that a piece was welded to the male side projecting from the contactor.

Does it now sound as though the compressor itself may not be the problem, but it may be a short in the contactor or does the new data regarding condensor indicate a bad winding/short in the condensor.

Is there any way of testing the contactor? I am thinking of removing it so I can see better what is going on. Perhaps it has a direct short somewhere I can't see with it mounted.

Is it possible that this could be caused by some badly burnt contacts? I am bnot certain, but it only seems to be popping the 50 A circuit breaker when both the lead from the load side of line 2 is connected to the run terminal of the compressor AND the lead from the load load side of line 1 is connected to the common terminal of the compressor.

I am guessing that means either the start winding nor the run winding is pulling enough amps to pop the 50 A CB by themselves, but together it pops immediatley.

If the contacts are badly burn would that cause a sudden surge that would immediately pop the breaker? It almost seems that its popping before either capacitor can charge.